HC Deb 08 May 1980 vol 984 cc217-8W
Mr. Ashley

asked the Secretary of State for Social Services (1) further to his reply to the right hon. Member for Stoke-on-Trent, South, at what level of degree of risk of danger to the foetus the Committee on Safety of Medicines refuses to give approval to a drug;

(2) further to his reply to the right hon. Member for Stoke-on-Trent, South, if the studies by Smithells and Sheppard and Shapiro, et al, used the same methods and criteria; if all of these studies were strictly comparable in clinical and statistical terms; and if he will define a clinically-significant increase in malformation, both in clinical and statistical terms.

Dr. Vaughan

There is little I can add to my previous reply to the right hon. Gentleman on 30 April.—[Vol. 983, c.525.]

The two controlled studies referred to by the right hon. Gentleman did not use the same methods and criteria and consequently cannot be regarded as strictly comparable. Both studies, however, found no evidence to implicate Debendox as a teratogenic agent causing malformation of the foetus. It is not practicable to give a single definition of what constitutes either a clinically or a statistically significant increase in malformations. Any such figure would depend upon the background incidence and pattern of congenital abnormalities in the population studied.